1. Field of the Invention
The present invention relates to a recording/reproducing apparatus including a digital memory device for recording not only major sound information such as voice messages but also auxiliary information such as date and telephone numbers in a sound form, so as to reproduce the major information in conjunction with the auxiliary information.
2. Description of Prior Art
In a small electronic appliance having recording functions, a magnetic recording tape and a disc are employed for recording voices, music and so on. Recently, a semiconductor random access memory (RAM) is utilized as a recording medium to record voice data and music data in a digital form. Such a semiconductor recording medium built in a small electronic appliance is known, for instance, from U.S. Pat. No. 4,391,530 to Wakabayashi, issued on July 5, 1983.
In this U.S. patent, a voice message is input to a time piece through an acoustic converter. Then the voice message signal is encoded by a predetermined sampling frequency into digital voice data. The voice data is sequentially stored in the semiconductor memory (RAM), while the memory addresses are successively used to designate the memory regions, so that the encoded voice message, or the voice data is sequentially stored, or recorded in the memory regions designated in RAM.
When the preset alarm time is reached, the memory regions of the semiconductor memory are sequentially addressed the same as in the recording mode so as to read out the voice data therefrom, thereby decoding the voice data to reproduce the stored voice message.
When a large memory such as capacity semiconductor memory a 32-Kbit random access memory is employed, and the sampling frequency is selected to be 4 KHz, the total recording/reproducing time amounts to approximately 8 seconds. In a conventional recording/reproducing apparatus, such a semiconductor memory having a large memory capacity cannot function at all when the alarm time is not preset, or no reproduction of the voice message is required when the preset alarm time is reached. Even if the voice message needs to be reproduced, if the recording time for this voice message is only about 5 seconds, a memory capacity of approximately 12 kilobits will not be used, i.e., approximately 3 seconds of the voice reproduction. This causes a waste of the available memory regions of the semiconductor memory.
It is therefore an object of the present invention to provide a recording/reproducing apparatus including a digital memory device, in which remaining memory regions that have not been used during the recording/reproducing modes are available for different data storing purposes.